| Sintra to Ifield | 960.85 mi (1,546.34 km) |
| Sintra to Ilford | 993.06 mi (1,598.18 km) |
| Sintra to Ilfracombe | 894.57 mi (1,439.67 km) |
| Sintra to Ilkeston | 1,051.86 mi (1,692.81 km) |
| Sintra to Ilkley | 1,104.09 mi (1,776.86 km) |
| Sintra to Immingham | 1,111.40 mi (1,788.63 km) |
| Sintra to Ince-in-Makerfield | 1,067.86 mi (1,718.56 km) |
| Sintra to Inverness | 1,311.42 mi (2,110.53 km) |
| Sintra to Inverurie | 1,315.64 mi (2,117.32 km) |
| Sintra to Ipswich | 1,046.72 mi (1,684.54 km) |
| Sintra to Irlam | 1,064.26 mi (1,712.76 km) |
| Sintra to Irthlingborough | 1,024.58 mi (1,648.90 km) |
| Sintra to Irvine | 1,182.52 mi (1,903.08 km) |
| Sintra to Islington | 988.11 mi (1,590.21 km) |
| Sintra to Iver | 978.03 mi (1,573.99 km) |
